The La Liga giants came into the Copa del Rey semi-final first leg on the back of a rare loss after being beaten by Valencia.
That 3-2 loss led to a nervous display against Sociedad, with Martino describing it as a risk-free display.
"A good game, we didn't take any risks. We were a bit apprehensive because of Saturday's game against Valencia," Martino said.
"We scored twice, probably thanks to chance and not because of how we played."
Sergio Busquets scored just before half-time with a scrappy goal and Sociedad had Inigo Martinez sent off soon after.
Sociedad goalkeeper Enaut Zubikarai scored a strange own goal on the hour-mark when his own midfielder Gorka Elustondo blasted an attempted clearance across goal and into him.
Martino said his team's finishing was costly against Valencia, while they never created enough to kill off the Copa del Rey tie.
"In the match against Valencia, in the first half, we played well but we didn't finish off well," he said.
"Today we didn't dominate to the point that would allow us to think we could have killed off the tie."
Superstar Lionel Messi again failed to find the net, with the Argentine now having scored just once in his past six matches.
"I'm not worried about Messi scoring goals," Martino said.
"He had three clear chances today, and one of them the 'keeper saved from point blank range – he'll score again soon."
